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1.
Nature ; 590(7846): 438-444, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33505029

RESUMEN

Long-term climate change and periodic environmental extremes threaten food and fuel security1 and global crop productivity2-4. Although molecular and adaptive breeding strategies can buffer the effects of climatic stress and improve crop resilience5, these approaches require sufficient knowledge of the genes that underlie productivity and adaptation6-knowledge that has been limited to a small number of well-studied model systems. Here we present the assembly and annotation of the large and complex genome of the polyploid bioenergy crop switchgrass (Panicum virgatum). Analysis of biomass and survival among 732 resequenced genotypes, which were grown across 10 common gardens that span 1,800 km of latitude, jointly revealed extensive genomic evidence of climate adaptation. Climate-gene-biomass associations were abundant but varied considerably among deeply diverged gene pools. Furthermore, we found that gene flow accelerated climate adaptation during the postglacial colonization of northern habitats through introgression of alleles from a pre-adapted northern gene pool. The polyploid nature of switchgrass also enhanced adaptive potential through the fractionation of gene function, as there was an increased level of heritable genetic diversity on the nondominant subgenome. In addition to investigating patterns of climate adaptation, the genome resources and gene-trait associations developed here provide breeders with the necessary tools to increase switchgrass yield for the sustainable production of bioenergy.


Asunto(s)
Aclimatación/genética , Biocombustibles , Genoma de Planta/genética , Genómica , Calentamiento Global , Panicum/genética , Poliploidía , Biomasa , Ecotipo , Evolución Molecular , Flujo Génico , Pool de Genes , Introgresión Genética , Anotación de Secuencia Molecular , Panicum/clasificación , Panicum/crecimiento & desarrollo , Estados Unidos
2.
PLoS Genet ; 19(2): e1010653, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36795790

RESUMEN

Animal traits develop through the expression and action of numerous regulatory and realizator genes that comprise a gene regulatory network (GRN). For each GRN, its underlying patterns of gene expression are controlled by cis-regulatory elements (CREs) that bind activating and repressing transcription factors. These interactions drive cell-type and developmental stage-specific transcriptional activation or repression. Most GRNs remain incompletely mapped, and a major barrier to this daunting task is CRE identification. Here, we used an in silico method to identify predicted CREs (pCREs) that comprise the GRN which governs sex-specific pigmentation of Drosophila melanogaster. Through in vivo assays, we demonstrate that many pCREs activate expression in the correct cell-type and developmental stage. We employed genome editing to demonstrate that two CREs control the pupal abdomen expression of trithorax, whose function is required for the dimorphic phenotype. Surprisingly, trithorax had no detectable effect on this GRN's key trans-regulators, but shapes the sex-specific expression of two realizator genes. Comparison of sequences orthologous to these CREs supports an evolutionary scenario where these trithorax CREs predated the origin of the dimorphic trait. Collectively, this study demonstrates how in silico approaches can shed novel insights on the GRN basis for a trait's development and evolution.


Asunto(s)
Drosophila melanogaster , Redes Reguladoras de Genes , Animales , Masculino , Femenino , Drosophila melanogaster/genética , Drosophila/genética , Factores de Transcripción/genética , Pigmentación/genética
3.
Plant J ; 116(4): 1003-1017, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37675609

RESUMEN

Populus species play a foundational role in diverse ecosystems and are important renewable feedstocks for bioenergy and bioproducts. Hybrid aspen Populus tremula × P. alba INRA 717-1B4 is a widely used transformation model in tree functional genomics and biotechnology research. As an outcrossing interspecific hybrid, its genome is riddled with sequence polymorphisms which present a challenge for sequence-sensitive analyses. Here we report a telomere-to-telomere genome for this hybrid aspen with two chromosome-scale, haplotype-resolved assemblies. We performed a comprehensive analysis of the repetitive landscape and identified both tandem repeat array-based and array-less centromeres. Unexpectedly, the most abundant satellite repeats in both haplotypes lie outside of the centromeres, consist of a 147 bp monomer PtaM147, frequently span >1 megabases, and form heterochromatic knobs. PtaM147 repeats are detected exclusively in aspens (section Populus) but PtaM147-like sequences occur in LTR-retrotransposons of closely related species, suggesting their origin from the retrotransposons. The genomic resource generated for this transformation model genotype has greatly improved the design and analysis of genome editing experiments that are highly sensitive to sequence polymorphisms. The work should motivate future hypothesis-driven research to probe into the function of the abundant and aspen-specific PtaM147 satellite DNA.


Asunto(s)
ADN Satélite , Populus , ADN Satélite/genética , Haplotipos/genética , Populus/genética , Ecosistema , Retroelementos , Centrómero/genética
4.
Plant Physiol ; 192(3): 2374-2393, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37018475

RESUMEN

The morphological diversity of the inflorescence determines flower and seed production, which is critical for plant adaptation. Hall's panicgrass (Panicum hallii, P. hallii) is a wild perennial grass that has been developed as a model to study perennial grass biology and adaptive evolution. Highly divergent inflorescences have evolved between the 2 major ecotypes in P. hallii, the upland ecotype (P. hallii var hallii, HAL2 genotype) with compact inflorescence and large seed and the lowland ecotype (P. hallii var filipes, FIL2 genotype) with an open inflorescence and small seed. Here we conducted a comparative analysis of the transcriptome and DNA methylome, an epigenetic mark that influences gene expression regulation, across different stages of inflorescence development using genomic references for each ecotype. Global transcriptome analysis of differentially expressed genes (DEGs) and co-expression modules underlying the inflorescence divergence revealed the potential role of cytokinin signaling in heterochronic changes. Comparing DNA methylome profiles revealed a remarkable level of differential DNA methylation associated with the evolution of P. hallii inflorescence. We found that a large proportion of differentially methylated regions (DMRs) were located in the flanking regulatory regions of genes. Intriguingly, we observed a substantial bias of CHH hypermethylation in the promoters of FIL2 genes. The integration of DEGs, DMRs, and Ka/Ks ratio results characterized the evolutionary features of DMR-associated DEGs that contribute to the divergence of the P. hallii inflorescence. This study provides insights into the transcriptome and epigenetic landscape of inflorescence divergence in P. hallii and a genomic resource for perennial grass biology.


Asunto(s)
Ecotipo , Panicum , Panicum/genética , Transcriptoma/genética , Inflorescencia/genética , Epigenoma/genética , Regulación de la Expresión Génica de las Plantas , Metilación de ADN/genética
5.
J Exp Zool B Mol Dev Evol ; 340(2): 143-161, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-34254440

RESUMEN

Changes in gene expression are a prominent feature of morphological evolution. These changes occur to hierarchical gene regulatory networks (GRNs) of transcription factor genes that regulate the expression of trait-building differentiation genes. While changes in the expression of differentiation genes are essential to phenotypic evolution, they can be caused by mutations within cis-regulatory elements (CREs) that drive their expression (cis-evolution) or within genes for CRE-interacting transcription factors (trans-evolution). Locating these mutations remains a challenge, especially when experiments are limited to one species that possesses the ancestral or derived phenotype. We investigated CREs that control the expression of the differentiation genes tan and yellow, the expression of which evolved during the gain, modification, and loss of dimorphic pigmentation among Sophophora fruit flies. We show these CREs to be necessary components of a pigmentation GRN, as deletion from Drosophila melanogaster (derived dimorphic phenotype) resulted in lost expression and lost male-specific pigmentation. We evaluated the ability of orthologous CRE sequences to drive reporter gene expression in species with modified (Drosophila auraria), secondarily lost (Drosophila ananassae), and ancestrally absent (Drosophila willistoni) pigmentation. We show that the transgene host frequently determines CRE activity, implicating trans-evolution as a significant factor for this trait's diversity. We validated the gain of dimorphic Bab transcription factor expression as a trans-change contributing to the dimorphic trait. Our findings suggest an amenability to change for the landscape of trans-regulators and begs for an explanation as to why this is so common compared to the evolution of differentiation gene CREs.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Masculino , Animales , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Drosophila/genética , Drosophila/metabolismo , Factores de Transcripción/genética , Pigmentación/genética , Fenotipo , Evolución Molecular
6.
Anesth Analg ; 136(1): 6-12, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35550391

RESUMEN

BACKGROUND: The representation of women among leaders in the field of anesthesia continues to trail that of their male counterparts. This qualitative study was conducted to understand the pathway of leadership acquisition among women in the field of anesthesiology. METHODS: Using constructivist grounded theory, we sought to determine whether there were specific internal or external factors that were common to women in leadership in the specialty field of anesthesiology, and specifically, how they obtained leadership positions. Semistructured interviews were conducted for data collection. A total of 26 women in leadership positions in anesthesiology participated in this study. RESULTS: The analysis of these interviews resulted in the development of 4 common themes related to career pathways for these women in leadership. Each theme was examined in depth to determine the qualities necessary for individuals to advance in the field and the pathway to obtaining leadership positions. The findings of this study showed that early-career, high-value mentorship and sponsorship were important factors in leadership acquisition. Most participants (n = 20; 76%) had early mentors. Of those with early mentorship, 13 (65%) had high-value mentors, who we define as someone with power or authority. Sponsorship was the leading factor contributing to leadership acquisition. CONCLUSIONS: The results of this qualitative study may serve as a guide for encouraging female anesthesiologists with leadership aspirations. We suggest that the specialty field of anesthesiology institute targeted measures to help increase the percentage of women leadership with formal sponsorship programs at the local and national levels.


Asunto(s)
Anestesiología , Liderazgo , Humanos , Masculino , Femenino , Factores Sexuales , Mentores , Procesos de Grupo
7.
Dev Biol ; 441(1): 159-175, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29981311

RESUMEN

A challenge for evolutionary research is to uncover how new morphological traits evolve the coordinated spatial and temporal expression patterns of genes that govern their formation during development. Detailed studies are often limited to characterizing how one or a few genes contributed to a trait's emergence, and thus our knowledge of how entire GRNs evolve their coordinated expression of each gene remains unresolved. The melanic color patterns decorating the male abdominal tergites of Drosophila (D.) melanogaster evolved in part by novel expression patterns for genes acting at the terminus of a pigment metabolic pathway, driven by cis-regulatory elements (CREs) with distinct mechanisms of Hox regulation. Here, we examined the expression and evolutionary histories of two important enzymes in this pathway, encoded by the pale and Ddc genes. We found that while both genes exhibit dynamic patterns of expression, a robust pattern of Ddc expression specifically evolved in the lineage of fruit flies with pronounced melanic abdomens. Derived Ddc expression requires the activity of a CRE previously shown to activate expression in response to epidermal wounding. We show that a binding site for the Grainy head transcription factor that promotes the ancestral wound healing function of this CRE is also required for abdominal activity. Together with previous findings in this system, our work shows how the GRN for a novel trait emerged by assembling unique yet similarly functioning CREs from heterogeneous starting points.


Asunto(s)
Proteínas de Drosophila/metabolismo , Factores de Transcripción GATA/metabolismo , Pigmentación/fisiología , Carácter Cuantitativo Heredable , Elementos de Respuesta/fisiología , Animales , Proteínas de Drosophila/genética , Drosophila melanogaster , Factores de Transcripción GATA/genética
8.
J Natl Compr Canc Netw ; 17(4): 297-301, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30959466

RESUMEN

Histologic transformation from adenocarcinoma to squamous cell carcinoma in lung cancer has not been reported as a mechanism of resistance to ALK inhibition. This report describes the clinical course of a female former light smoker with metastatic lung adenocarcinoma whose tumor underwent histologic transformation from a well-differentiated lung adenocarcinoma to a well-differentiated lung squamous cell carcinoma in the same location at the left mainstem bronchus while maintaining the ALK fusion oncogene without any resistance mutations. After experiencing disease progression while on crizotinib, the patient participated in clinical trials that provided early access to the novel ALK inhibitors ceritinib and alectinib before they were commercially available. Tumor recurrence occurred at the primary and metastatic central nervous system sites (ie, brain and spine). At tumor progression, liquid biopsy and tumor genomic profiling of plasma cell-free DNA next-generation sequencing (NGS) provided an accurate diagnosis with a short turnaround time compared with the tissue-based targeted capture NGS. The patient received several courses of radiation primarily to the brain and spine during her disease course. Her disease did not respond to the immune checkpoint inhibitor nivolumab, and she died on home hospice approximately 4 years after diagnosis. This case supports the importance of both histopathologic assessment and comprehensive genomic profiling in selecting appropriate treatment for patients with refractory, metastatic, ALK oncogene-driven non-small cell lung cancer. Use of symptom-directed radiation in tandem with ALK inhibitors contributed to the disease and symptomatic control and prolonged survival in this patient.


Asunto(s)
Adenocarcinoma del Pulmón/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Proteínas de Fusión Oncogénica/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Humanos
9.
BMC Public Health ; 19(1): 1521, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31727039

RESUMEN

BACKGROUND: Improving the rates of, and instruments used in, screening for perinatal depression and anxiety among Aboriginal and Torres Strait Islander women are important public health priorities. The Kimberley Mum's Mood Scale (KMMS) was developed and later validated as an effective and acceptable perinatal depression and anxiety screening tool for the Kimberley region under research conditions. Other regions have expressed interest in using the KMMS with perinatal Aboriginal and Torres Strait Islander women. It is, however, important to re-evaluate the KMMS in a larger Kimberley sample via a real world implementation study, and to test for applicability in other remote and regional environments before recommendations for wider use can be made. This paper outlines the protocol for evaluating the process of implementation and establishing the 'real world' validity and acceptability of the KMMS in the Kimberley, Pilbara and Far North Queensland in northern Australia. METHODS: The study will use a range of quantitative and qualitative methods across all sites. KMMS validation/revalidation internal consistency of Part 1 will be determined using Cronbach's alpha. Equivalence for identifying risk of depression and anxiety compared to a standard reference assessment will be determined from receiver operating characteristic curves. Sensitivity and specificity will be determined based on these cut-points. Qualitative methods of phenomenology will be used to explore concepts of KMMS user acceptability (women and health professionals). Additional process evaluation methods will collate, assess and report on KMMS quality review data, consultations with health service administrators and management, field notes, and other documentation from the research team. This information will be reported on using the Dynamic Sustainability Framework. DISCUSSION: This project is contributing to the important public health priority of screening Aboriginal and Torres Strait Islander women for perinatal depression and anxiety with tools that are meaningful and responsive to cultural and clinical needs. Identifying and addressing barriers to implementation contributes to our understanding of the complexity of improving routine clinical practie. TRIAL REGISTRATION: The study was registered retrospectively on 15/05/2019 with the Australian and New Zealand Clinical Trial registry (ACTRN12619000580178).


Asunto(s)
Afecto , Ansiedad/diagnóstico , Depresión/diagnóstico , Tamizaje Masivo/métodos , Salud Mental/etnología , Nativos de Hawái y Otras Islas del Pacífico/psicología , Atención Perinatal/métodos , Adolescente , Adulto , Ansiedad/etnología , Depresión/etnología , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/etnología , Femenino , Humanos , Lactante , Recién Nacido , Islas , Tamizaje Masivo/normas , Madres/psicología , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/etnología , Mujeres Embarazadas/etnología , Mujeres Embarazadas/psicología , Psicometría , Queensland , Proyectos de Investigación , Estudios Retrospectivos , Adulto Joven
10.
J Virol ; 91(11)2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28331094

RESUMEN

Herpes simplex virus (HSV) anterograde transport in neuronal axons is vital, allowing spread from latently infected ganglia to epithelial tissues, where viral progeny are produced in numbers allowing spread to other hosts. The HSV membrane proteins gE/gI and US9 initiate the process of anterograde axonal transport, ensuring that virus particles are transported from the cytoplasm into the most proximal segments of axons. These proteins do not appear to be important once HSV is inside axons. We previously described HSV double mutants lacking both gE and US9 that failed to transport virus particles into axons. Here we show that gE- US9- double mutants accumulate large quantities of unenveloped and partially enveloped capsids in neuronal cytoplasm. These defects in envelopment can explain the defects in axonal transport of enveloped virions. In addition, the unenveloped capsids that accumulated were frequently bound to cytoplasmic membranes, apparently immobilized in intermediate stages of envelopment. A gE-null mutant produced enveloped virions, but these accumulated in large numbers in the neuronal cytoplasm rather than reaching cell surfaces as wild-type HSV virions do. Thus, in addition to the defects in envelopment, there was missorting of capsids and enveloped particles in the neuronal cytoplasm, which can explain the reduced anterograde transport of unenveloped capsids and enveloped virions. These mechanisms differ substantially from existing models suggesting that gE/gI and US9 function by tethering HSV particles to kinesin microtubule motors. The defects in assembly of gE- US9- mutant virus particles were novel because they were neuron specific, in keeping with observations that US9 is neuron specific.IMPORTANCE Herpes simplex virus (HSV) and other alphaherpesviruses, such as varicella-zoster virus, depend upon the capacity to navigate in neuronal axons. To do this, virus particles tether themselves to dyneins and kinesins that motor along microtubules from axon tips to neuronal cell bodies (retrograde transport) or from cell bodies to axon tips (anterograde transport). This transit in axons is essential for alphaherpesviruses to establish latency in ganglia and then to reactivate and move back to peripheral tissues for spread to other hosts. Anterograde transport of HSV requires two membrane proteins: gE/gI and US9. Our studies reveal new mechanisms for how gE/gI and US9 initiate anterograde axonal transport. HSV mutants lacking both gE and US9 fail to properly assemble enveloped virus particles in the cytoplasm, which blocks anterograde transport of enveloped particles. In addition, there are defects in the sorting of virus particles such that particles, when formed, do not enter proximal axons.


Asunto(s)
Axones/metabolismo , Citoplasma/virología , Lipoproteínas/genética , Lipoproteínas/metabolismo , Neuronas/virología , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Simplexvirus/fisiología , Proteínas del Envoltorio Viral/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismo , Animales , Transporte Axonal , Axones/virología , Cápside/fisiología , Línea Celular , Chlorocebus aethiops , Péptidos y Proteínas de Señalización Intracelular , Cinesinas/metabolismo , Mutación , Neuronas/fisiología , Transporte de Proteínas , Simplexvirus/genética , Simplexvirus/metabolismo , Células Vero , Proteínas del Envoltorio Viral/genética , Virión/genética , Virión/metabolismo
11.
Int J Syst Evol Microbiol ; 67(5): 1442-1450, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28150571

RESUMEN

A novel psychrotolerant bacterium, strain ISLP-3T, was isolated from a sample of naturally formed ice sculpture on the shore of Lake Podprudnoye in Antarctica. Cells were motile, stained Gram-positive, non-spore-forming, straight or slightly curved rods with the shape of a baseball bat. The new isolate was facultatively anaerobic and catalase-positive. Growth occurred at 3-35 °C with an optimum at 22-24 °C, 0-2 % (w/v) NaCl with an optimum at 0.3 % and pH 6.2-9.5 with an optimum at pH 7.5. Strain ISLP-3T grew on several carbon sources, with the best growth on cellobiose. The isolate possessed ureolytic activity but growth was inhibited by urea. The strain was sensitive to: ampicillin, gentamycin, kanamycin rifampicin, tetracycline and chloramphenicol. Major fatty acids were: anteiso-C15 : 0, iso-C16 : 0, C16 : 0, C14 : 0 and iso-C15 : 0. The predominant menaquinone was MK-9(H4). The genomic G+C content was 69.5 mol%. The 16S rRNA gene showed 99 % sequence similarity to that of Sanguibacter suarezii ST-26T, but their recA genes shared ≤91 % sequence similarity, suggesting that this new isolate represents a novel species within the genus Sanguibacter. This conclusion was supported by average nucleotide identity, which was ≤91 % to the most closely related strain. The name Sanguibacter gelidistatuariae sp. nov. is proposed for the novel species with the type strain ISLP-3T=ATCC TSD-17T=DSM 100501T=JCM 30887T). The complete genome draft sequence of ISLP-3T was deposited under IMG OID 2657245272. Emendments to the descriptions of related taxa have been made based on experimental data from our comparative analysis.


Asunto(s)
Actinomycetales/clasificación , Hielo , Filogenia , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Regiones Antárticas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , ARN Ribosómico 16S/genética , Escultura , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
J Neurosci ; 35(33): 11682-93, 2015 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-26290245

RESUMEN

The nociceptin/orphanin FQ (NOP) receptor, the fourth member of the opioid receptor family, is involved in many processes common to the opioid receptors including pain and drug abuse. To better characterize receptor location and trafficking, knock-in mice were created by inserting the gene encoding enhanced green fluorescent protein (eGFP) into the NOP receptor gene (Oprl1) and producing mice expressing a functional NOP-eGFP C-terminal fusion in place of the native NOP receptor. The NOP-eGFP receptor was present in brain of homozygous knock-in animals in concentrations somewhat higher than in wild-type mice and was functional when tested for stimulation of [(35)S]GTPγS binding in vitro and in patch-clamp electrophysiology in dorsal root ganglia (DRG) neurons and hippocampal slices. Inhibition of morphine analgesia was equivalent when tested in knock-in and wild-type mice. Imaging revealed detailed neuroanatomy in brain, spinal cord, and DRG and was generally consistent with in vitro autoradiographic imaging of receptor location. Multicolor immunohistochemistry identified cells coexpressing various spinal cord and DRG cellular markers, as well as coexpression with µ-opioid receptors in DRG and brain regions. Both in tissue slices and primary cultures, the NOP-eGFP receptors appear throughout the cell body and in processes. These knock-in mice have NOP receptors that function both in vitro and in vivo and appear to be an exceptional tool to study receptor neuroanatomy and correlate with NOP receptor function. SIGNIFICANCE STATEMENT: The NOP receptor, the fourth member of the opioid receptor family, is involved in pain, drug abuse, and a number of other CNS processes. The regional and cellular distribution has been difficult to determine due to lack of validated antibodies for immunohistochemical analysis. To provide a new tool for the investigation of receptor localization, we have produced knock-in mice with a fluorescent-tagged NOP receptor in place of the native NOP receptor. These knock-in mice have NOP receptors that function both in vitro and in vivo and have provided a detailed characterization of NOP receptors in brain, spinal cord, and DRG neurons. They appear to be an exceptional tool to study receptor neuroanatomy and correlate with NOP receptor function.


Asunto(s)
Proteínas Fluorescentes Verdes/metabolismo , Microscopía Fluorescente/métodos , Neuronas/citología , Neuronas/metabolismo , Receptores Opioides/metabolismo , Fracciones Subcelulares/metabolismo , Animales , Células Cultivadas , Técnicas de Sustitución del Gen , Proteínas Fluorescentes Verdes/genética , Masculino , Ratones , Ratones Transgénicos , Imagen Molecular/métodos , Receptores Opioides/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Fracciones Subcelulares/ultraestructura , Distribución Tisular , Receptor de Nociceptina
13.
Eur J Nucl Med Mol Imaging ; 43(13): 2353-2359, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27315059

RESUMEN

PURPOSE: To assess the feasibility of conducting pretreatment mesenteric angiography, coil embolization, 99mTc macroaggregated albumin (99mTc-MAA) scintigraphy, and 90Y radioembolization treatment in a single, same-day, combined outpatient encounter. METHODS: This was a retrospective study of 78 patients treated during the period 2008 - 2015 who were managed in a single outpatient encounter under the guidance of the Interventional Radiology Department and The Nuclear Medicine Department. Pretreatment planning was performed by reviewing baseline imaging and estimated perfused liver volume bearing the tumor. The region of interest was estimated using 3-D software; this value was used for dosimetry planning. Maximum lung shunting fractions of 10 % for hepatocellular carcinoma and 5 % for liver metastases were assumed. Subsequently, hepatic angiography and 99mTc-MAA scintigraphy were performed followed by 90Y treatment in one outpatient encounter. Total in-room procedure time was recorded. RESULTS: All patients underwent same-day angiography, 99mTc-MAA scintigraphy and 90Y radioembolization. Of the 78 patients, 16 received multiple segmental treatments to both lobes, 44 received treatment to the right lobe, and 18 received treatment to the left lobe. The median dose was 106 Gy. The median number of 90Y vials needed was two (range one to six). The median in-room time was 160 min (75 - 250 min). The residential status of the patients was as follows, 18 % (14/78) were local residents, 55 % (43/78) traveled from outside the city limits, 18 % (14/78) were from out-of-state, and 9 % (7/78) were resident abroad. Of the 78 patients, 61 (77 %) had hepatocellular carcinoma, and 17 (22 %) had liver metastases. The median lung dose was 3.5 Gy. CONCLUSION: This study demonstrated the feasibility of same-day 90Y evaluation and treatment while maintaining the principles of safe and effective 90Y infusion including tumoricidal dosimetry (lobar, segmentectomy), minimization of nontarget flow, and minimization of lung dose. This paradigm translates into expeditious cancer care and significant cost savings.


Asunto(s)
Terapia Combinada/métodos , Embolización Terapéutica/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Radioisótopos de Itrio/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento
14.
Clin Transplant ; 30(12): 1578-1583, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27726211

RESUMEN

BACKGROUND: Acute hypothyroidism after brain death results in hemodynamic impairments that limit availability of donor hearts. Thyroid hormone infusions can halt that process and lead to increased utilization of donor organs, but prolonged use of thyroid replacement has not been well studied. METHODS: We developed a 15-question survey regarding policies, procedures, and reporting of thyroid hormone use by organ procurement organizations (OPOs). The survey was posted for 5 weeks on the Association of OPOs Portal. RESULTS: We received 29 responses, representing 24 OPOs. Seventy-two percent reported their OPOs use thyroid hormone for all potential donors and 90% have a protocol for thyroid hormone use. There is a large variation in the maximum dose of thyroid hormone used, and many OPOs have no weaning protocol. Most OPOs do not collect data on total thyroid hormone administered during procurement and would favor more detailed report of thyroid hormone use. CONCLUSIONS: Thyroid hormone use can have important implications for organ selection and cardiac function before and after transplantation. Protocols vary widely with respect to why and how to use and wean thyroid hormone. We believe there should be more detailed reporting of thyroid hormone use for future studies to ensure appropriate donor management.


Asunto(s)
Muerte Encefálica , Hipotiroidismo/prevención & control , Pautas de la Práctica en Medicina/estadística & datos numéricos , Hormonas Tiroideas/uso terapéutico , Obtención de Tejidos y Órganos/métodos , Protocolos Clínicos , Encuestas de Atención de la Salud , Humanos , Hipotiroidismo/etiología , Guías de Práctica Clínica como Asunto , Estados Unidos
15.
Eur J Neurosci ; 42(12): 3018-32, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26390912

RESUMEN

GABA is a principal neurotransmitter in the suprachiasmatic hypothalamic nucleus (SCN), the master circadian clock. Despite the importance of GABA and GABA uptake for functioning of the circadian pacemaker, the localization and expression of GABA transporters (GATs) in the SCN has not been investigated. The present studies used Western blot analysis, immunohistochemistry and electron microscopy to demonstrate the presence of GABA transporter 1 (GAT1) and GAT3 in the SCN. By using light microscopy, GAT1 and GAT3 were co-localized throughout the SCN, but were not expressed in the perikarya of arginine vasopressin- or vasoactive intestinal peptide-immunoreactive (-ir) neurons of adult rats, nor in the neuronal processes labelled with the neurofilament heavy chain. Using electron microscopy, GAT1- and GAT3-ir was found in glial processes surrounding unlabelled neuronal perikarya, axons, dendrites, and enveloped symmetric and asymmetric axo-dendritic synapses. Glial fibrillary acidic protein-ir astrocytes grown in cell culture were immunopositive for GAT1 and GAT3 and both GATs could be observed in the same glial cell. These data demonstrate that synapses in the SCN function as 'tripartite' synapses consisting of presynaptic axon terminals, postsynaptic membranes and astrocytes that contain GABA transporters. This model suggests that astrocytes expressing both GATs may regulate the extracellular GABA, and thereby modulate the activity of neuronal networks in the SCN.


Asunto(s)
Astrocitos/metabolismo , Proteínas Transportadoras de GABA en la Membrana Plasmática/metabolismo , Neuronas/metabolismo , Núcleo Supraquiasmático/metabolismo , Animales , Arginina Vasopresina/metabolismo , Astrocitos/ultraestructura , Western Blotting , Células Cultivadas , Ritmo Circadiano/fisiología , Proteína Ácida Fibrilar de la Glía/metabolismo , Inmunohistoquímica , Masculino , Microscopía Electrónica , Neuronas/ultraestructura , Ratas Sprague-Dawley , Núcleo Supraquiasmático/ultraestructura , Péptido Intestinal Vasoactivo/metabolismo
16.
Eur J Nucl Med Mol Imaging ; 42(13): 2038-44, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26194715

RESUMEN

PURPOSE: Radioembolization with (90)Y microspheres is a locoregional radiation therapy for unresectable hepatic neoplasm. Non-target delivery of (90)Y microspheres resulting in gastrointestinal (GI) symptoms is a recognized complication; there is minimal knowledge regarding the radiation effect to the gastric wall from left hepatic lobe (90)Y treatments. Our aim was to study the incidence of GI complications when the target tissue (hepatic parenchyma ± tumor) is in close proximity to the gastric wall. We hypothesized that liver (tumor) to stomach proximity does not correlate with increased toxicity. METHODS: Between November 2011 and September 2013, we studied all patients who underwent left lobe radioembolization with (90)Y glass microspheres. With Institutional Review Board (IRB) approval, we retrospectively reviewed MRI/CT images of these patients, identifying a subset of patients with the left hepatic lobe <1 cm from the gastric wall. Patients were seen in clinic 1 month posttreatment and subsequently at 3-month intervals. Short- and long-term gastric adverse events were tabulated. RESULTS: Ninety-seven patients successfully underwent left hepatic lobe (90)Y microsphere radioembolization in which the average distance from the liver to the stomach wall was 1.0 ± 2.8 mm. The average dose for patients who received radioembolization to the left hepatic lobe was 109 ± 57 Gy. Fifty patients had tumor within 1 cm of the gastric wall. The average dose for patients who received radioembolization to the left hepatic lobe with tumor within 1 cm of the gastric wall was 121 ± 41 Gy. There were no reportable or recordable medical events. Of the patients, 34% reported abdominal pain that was grade 1-2; 65% of the patients reported no abdominal pain. None of the 97 patients developed a clinically evident GI ulcer. CONCLUSION: Patients with left lobe tumors adjacent to or abutting the stomach do not exhibit acute or chronic radiation effects following radioembolization with glass microspheres.


Asunto(s)
Neoplasias Hepáticas/radioterapia , Traumatismos por Radiación/etiología , Radiofármacos/efectos adversos , Úlcera Gástrica/etiología , Radioisótopos de Itrio/efectos adversos , Embolización Terapéutica/efectos adversos , Humanos , Microesferas , Radiofármacos/administración & dosificación , Radiofármacos/uso terapéutico , Radioisótopos de Itrio/administración & dosificación , Radioisótopos de Itrio/uso terapéutico
18.
Dev Biol ; 382(1): 70-81, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23916849

RESUMEN

In the frog Xenopus laevis, dorsal-ventral axis specification involves cytoskeleton-dependent transport of localized transcripts and proteins during the first cell cycle, and activation of the canonical Wnt pathway to locally stabilize translated beta-catenin which, by as early as the 32-cell stage, commits nuclei in prospective dorsal lineages to the subsequent expression of dorsal target genes. Maternal ligands important for activating this dorsal-specific signaling pathway are thought to interact with secreted glypicans and coreceptors in the blastocoel. While diffusion between cells is generally thought of as sufficient to accomplish the distribution of secreted maternal ligands to their appropriate targets, signaling may also involve other potential mechanisms, including direct transfer of morphogens via membrane-bounded entities, such as argosomes, exosomes, or even filopodia. In Xenopus, the blastocoel-facing, basolateral surfaces where signaling interactions ostensibly take place have not been previously examined in detail. Here, we report that the cleavage-stage blastocoel is traversed by hundreds of extremely long cellular protrusions that maintain long-term contacts between nonadjacent blastomeres during expansion of the interstitial space in early embryogenesis. The involvement of these protrusions in early embryonic patterning is suggested by the discoveries that (a) they fragment into microvesicles, whose resorption facilitates considerable exchange of cytoplasm and membrane between blastomeres; and (b) they are active in caveolar endocytosis, a prerequisite for ligand-receptor signaling.


Asunto(s)
Fase de Segmentación del Huevo/metabolismo , Seudópodos/metabolismo , Transducción de Señal , Xenopus laevis/embriología , Ácidos/metabolismo , Animales , Blastómeros/citología , Blastómeros/metabolismo , Fase de Segmentación del Huevo/citología , Fase de Segmentación del Huevo/ultraestructura , Vesículas Citoplasmáticas/metabolismo , Vesículas Citoplasmáticas/ultraestructura , Embrión no Mamífero/ultraestructura , Endocitosis , Fusión de Membrana , Seudópodos/ultraestructura , Xenopus laevis/metabolismo
19.
Eur J Nucl Med Mol Imaging ; 41(10): 1861-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24906565

RESUMEN

PURPOSE: The aim of this study was to analyze the safety, treatment characteristics and survival outcomes of Yttrium-90 (Y90) radioembolization for unresectable colorectal carcinoma (CRC) liver metastases refractory to standard of care therapy. METHODS: A total of 214 patients with CRC metastases were treated with Y90 radioembolization over 12 years. Toxicity was assessed using National Cancer Institute common terminology criteria. Overall survival was analyzed from date of diagnosis of primary cancer, hepatic metastases and from the first Y90. Uni/multivariate analyses were performed. Substratification by era of chemotherapeutics was performed. RESULTS: Most patients were male (60 %) and <65 years old (61 %). Of them, 98 % had been exposed to chemotherapy. Grade 3 lymphocyte, bilirubin, albumin, ALP and AST toxicities were observed in 39 %, 11 %, 10 %, 8 % and 4 % of patients, respectively. Grade 4 lymphocyte and ALP toxicities were observed in 5 % and 3 % of patients, respectively. Median overall survival was 43.0, 34.6, and 10.6 months from date of diagnosis of primary cancer, hepatic metastases and first Y90, respectively. Survival was significantly longer in patients: (1) who received ≤2 cytotoxic drugs (n = 104) than those who received 3 (n = 110) (15.2 vs. 7.5 months, p = 0.0001); and (2) who received no biologic agents (n = 52) compared with those that did (n = 162) (18.6 vs. 9.4 months, p = 0.0001). Multivariate analyses identified ≤2 cytotoxic agents, no exposure to biologics, ECOG 0, tumor burden <25 %, lack of extrahepatic disease and albumin >3 g/dL as independent predictors of survival. CONCLUSION: In this largest metastatic CRC series published to date, Y90 radioembolization was found to be safe; survival varied by prior therapy. Further studies are required to further refine the role of Y90 in metastatic CRC.


Asunto(s)
Carcinoma/secundario , Quimioradioterapia , Neoplasias Colorrectales/secundario , Neoplasias Hepáticas/terapia , Radiofármacos/uso terapéutico , Radioisótopos de Itrio/uso terapéutico , Anciano , Embolización Terapéutica/efectos adversos , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Radiofármacos/efectos adversos , Análisis de Supervivencia , Radioisótopos de Itrio/efectos adversos
20.
J Vasc Interv Radiol ; 25(2): 266-70, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24332243

RESUMEN

PURPOSE: To investigate the feasibility of yttrium-90 ((90)Y) glass microsphere radioembolization (including angiography, lung shunt assessment, and treatment) as a single-session, outpatient procedure. MATERIALS AND METHODS: Between January 2008 and June 2013, 14 patients underwent outpatient, single-session radioembolization with (90)Y glass microspheres. As part of the routine diagnostic work-up, all patients underwent either computed tomography (CT) or magnetic resonance imaging of the liver with three-dimensional analysis and had laboratory results forwarded to our center for confirmation of candidacy before treatment. On treatment day, all patients underwent planning mesenteric angiography with flat panel cone-beam CT imaging. Patients were administered 33-85 MBq of technetium-99m macroaggregated albumin ((99m)Tc-MAA) via a microcatheter positioned in a hepatic artery supplying the tumor of interest. Planar scintigraphy was initiated within 2 hours after the administration of (99m)Tc-MAA and lung shunt fraction was determined. Final dosimetry calculations were performed while the patient was being transferred back from nuclear medicine to interventional radiology. RESULTS: All patients successfully underwent planning angiography with administration of (99m)Tc-MAA and (90)Y radioembolization as a single-session treatment. There were no reportable or recordable medical events; treatment was carried out to the desired dose in all cases. The mean total procedure time was 2.70 hours ± 0.72 (range, 1.63-3.97 h). CONCLUSIONS: This study reports a novel proof of concept for performing radioembolization in a single-session setting. By using the described method, time between initial clinical assessments and radioembolization treatment is decreased, and costs are minimized.


Asunto(s)
Embolización Terapéutica/métodos , Vidrio , Neoplasias Hepáticas/radioterapia , Radiofármacos/administración & dosificación , Radioisótopos de Itrio/administración & dosificación , Atención Ambulatoria , Angiografía de Substracción Digital , Embolización Terapéutica/efectos adversos , Estudios de Factibilidad , Humanos , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética , Microesferas , Radiografía Intervencional , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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